[Federal Register Volume 60, Number 149 (Thursday, August 3, 1995)]
[Rules and Regulations]
[Pages 39628-39631]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-18434]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-NM-126-AD; Amendment 39-9320; AD 95-16-01]
Airworthiness Directives; McDonnell Douglas Model MD-11 Series
Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment supersedes an existing airworthiness directive
(AD), applicable to all McDonnell Douglas Model MD-11 series airplanes,
that currently requires a revision to the Airplane Flight Manual (AFM)
that prohibits autoland operation below 100 feet above ground level,
and installation of flight control computer software. It also provides
for an optional terminating action for the AFM revision. This amendment
provides for a new optional terminating action for the AFM revision.
This amendment is prompted by reports of erroneous central aural
warning system altitude callouts and erroneous radio altimeter
indications during autoland approaches due to radio frequency leakage
(RF) on airplanes on which the optional terminating action had been
accomplished. The actions specified in this AD are intended to prevent
radio altimeter antenna/coaxial cable RF leakage, which could result in
early and/or abnormal flare (pitch) control during autoland operation
and potential degradation of the landing capability of the airplane.
DATES: Effective August 18, 1995.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director
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of the Federal Register as of August 18, 1995.
The incorporation by reference of McDonnell Douglas MD-11 Alert
Service Bulletin A34-57, dated December 19, 1994, as listed in the
regulations, was approved previously by the Director of the Federal
Register as of February 6, 1995 (60 FR 4076, January 20, 1995).
Comments for inclusion in the Rules Docket must be received on or
before October 2, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-126-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.
The service information referenced in this AD may be obtained from
McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach,
California 90846, Attention: Technical Publications Business
Administration, Dept. C1-L51 (2-60). This information may be examined
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW.,
Renton, Washington; or at the FAA, Transport Airplane Directorate, Los
Angeles Aircraft Certification Office, 3960 Paramount Boulevard,
Lakewood, California; or at the Office of the Federal Register, 800
North Capitol Street, NW., suite 700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Brett Portwood, Aerospace Engineer,
Systems and Equipment Branch, ANM-130L, FAA, Transport Airplane
Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount
Boulevard, Lakewood, California 90712; telephone (310) 627-5347; fax
(310) 627-5210.
SUPPLEMENTARY INFORMATION: On January 6, 1995, the FAA issued AD 94-26-
51, amendment 39-9120 (60 FR 4076, January 20, 1995), applicable to all
McDonnell Douglas Model MD-11 series airplanes. It requires a revision
to the Limitations Section of the FAA-approved Airplane Flight Manual
(AFM) to prohibit autoland operation below 100 feet above ground level
(AGL), and installation of -905 flight control computer (FCC) software.
It also provides for an optional terminating action for the AFM
revision, consisting of certain inspections and tests. That action was
prompted by reports of a loose nut on a coaxial connector on a radio
altimeter receiver/transmitter rack, and the transmittal of erroneous
altitude data to the FCC while the airplane was below 100 feet AGL,
which resulted in abnormal flare (pitch) control during autoland
operation. The actions required by that AD are intended to prevent
abnormal flare (pitch) control, which could result in degradation of
the landing capability of the airplane.
Since the issuance of that AD, the FAA has received several reports
of erroneous central aural warning system (CAWS) altitude callouts and
erroneous radio altimeter indications during autoland approaches on
Model MD-11 series airplanes. Investigation has revealed that these
incidents occurred on these airplanes following accomplishment of the
optional terminating action (inspections and tests) and the
installation of the -905 FCC software, as specified in AD 94-26-51. In
light of these incidents, the FAA has determined that those provisions
of AD 94-26-51 do not adequately preclude radio frequency (RF) leakage
of the radio altimeter antenna/coaxial cable. That condition could
result in abnormal flare (pitch) control during autoland operation and
potential degradation of the landing capability of the airplane.
Additionally, since the issuance of AD 94-26-51, McDonnell Douglas
has developed a new, improved modification to the FCC software for
Model MD-11 series airplanes. Further, Allied Signal has developed a
new, improved modification to the radio altimeter.
The FAA has reviewed and approved McDonnell Douglas Service
Bulletin MD11-34-063, dated July 10, 1995, which describes procedures
for replacement of the radio altimeters 1 and 2 located in the center
accessory compartment with modified radio altimeters, for certain
airplanes. The modified radio altimeters are less susceptible to
influence by antenna/coaxial system RF leakage.
The FAA has also reviewed and approved McDonnell Douglas Service
Bulletin MD11-34-060, Revision 3, dated July 14, 1995, which describes
procedures for:
1. Performing an inspection to identify the part number (P/N) of
the coaxial cables of the radio altimeter;
2. Installing new clamps, replacing the cables with new cables,
performing an inspection to verify if lockwashers having P/N MS51848-45
are installed on the coaxial contacts, and various follow-on actions;
and
3. Installing new clamps on certain airplanes, and replacing and
relocating the brackets of the terminal grounding block on certain
other airplanes, if any cable is identified as P/N AE11919-1, -2, -3,
or -4.
These procedures will minimize the possibility of RF signal
leakage. The service bulletin specifies that these actions be
accomplished within 7 months.
Additionally, the FAA has reviewed and approved McDonnell Douglas
Service Bulletin MD11-22-015, dated July 3, 1995, which describes
procedures for updating the software of two flight control computers
(FCC) having part number (P/N) 4059001-904 or -905 and reidentifying
them as P/N 4059001-906. This update will minimize the effects of radio
altimeter signal leakage. Accomplishment of the update and
reidentification constitutes terminating action for the AFM revision.
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of this same type design, this AD
supersedes AD 94-26-51 to continue to require a revision to the
Limitations Section of the FAA-approved AFM to prohibit autoland
operation below 100 feet AGL. However, this AD provides for a new
optional terminating action, which would constitute terminating action
for the AFM revision and the temporary optional terminating action
(repetitive inspections and tests, which have been retained from AD 94-
26-51). Operators electing to accomplish the new terminating action
will be required to perform it in accordance with procedures described
in the service bulletins described previously. This AD also requires
that operators report results of inspection findings, positive or
negative, to the FAA.
Operators who currently are accomplishing the terminating action
specified in AD 94-26-51 should note that, although McDonnell Douglas
Service Bulletin MD11-34-060 recommends accomplishment of the described
procedures within 7 months, this AD requires their accomplishment
within 60 days. The FAA finds that continuing to perform the previous
terminating actions for a period of 7 months would not address the
identified unsafe condition in a timely manner. In developing an
appropriate compliance time for this AD, the FAA considered not only
the degree of urgency associated with addressing the subject unsafe
condition, but the upcoming inclement weather conditions and the
maximum interval of time allowable for all affected airplanes to
continue to operate without compromising safety. The FAA finds 60 days
to be an appropriate compliance time for initiating these new
terminating actions.
As a result of recent communications with the Air Transport
Association (ATA) of America, the FAA has learned that, in general,
some operators may
[[Page 39630]]
misunderstand the legal effect of AD's on airplanes that are identified
in the applicability provision of the AD, but that have been altered or
repaired in the area addressed by the AD. The FAA points out that all
airplanes identified in the applicability provision of an AD are
legally subject to the AD. If an airplane has been altered or repaired
in the affected area in such a way as to affect compliance with the AD,
the owner or operator is required to obtain FAA approval for an
alternative method of compliance with the AD, in accordance with the
paragraph of each AD that provides for such approvals. A note has been
included in this rule to clarify this long-standing requirement.
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting flight safety and, thus, was not preceded by
notice and an opportunity for public comment, comments are invited on
this rule. Interested persons are invited to comment on this rule by
submitting such written data, views, or arguments as they may desire.
Communications shall identify the Rules Docket number and be submitted
in triplicate to the address specified under the caption ADDRESSES. All
communications received on or before the closing date for comments will
be considered, and this rule may be amended in light of the comments
received. Factual information that supports the commenter's ideas and
suggestions is extremely helpful in evaluating the effectiveness of the
AD action and determining whether additional rulemaking action would be
needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the rule. All comments submitted will be
available, both before and after the closing date for comments, in the
Rules Docket for examination by interested persons. A report that
summarizes each FAA-public contact concerned with the substance of this
AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this rule must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 95-NM-126-AD.'' The postcard will be date stamped and
returned to the commenter.
The regulations adopted herein will not have substantial direct
effects on the States, on the relationship between the national
government and the States, or on the distribution of power and
responsibilities among the various levels of government. Therefore, in
accordance with Executive Order 12612, it is determined that this final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
The FAA has determined that this regulation is an emergency
regulation that must be issued immediately to correct an unsafe
condition in aircraft, and that it is not a ``significant regulatory
action'' under Executive Order 12866. It has been determined further
that this action involves an emergency regulation under DOT Regulatory
Policies and Procedures (44 FR 11034, February 26, 1979). If it is
determined that this emergency regulation otherwise would be
significant under DOT Regulatory Policies and Procedures, a final
regulatory evaluation will be prepared and placed in the Rules Docket.
A copy of it, if filed, may be obtained from the Rules Docket at the
location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends part 39 of
the Federal Aviation Regulations (14 CFR part 39) as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by removing amendment 39-9120 (60 FR
4076, January 20, 1995), and by adding a new airworthiness directive
(AD), amendment 39-9320, to read as follows:
95-16-01 McDonnell Douglas: Amendment 39-9320. Docket 95-NM-126-AD.
Supersedes AD 94-26-51, Amendment 39-9120.
Applicability: All Model MD-11 series airplanes, certificated in
any category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
modified, altered, or repaired in the area subject to the
requirements of this AD. For airplanes that have been modified,
altered, or repaired so that the performance of the requirements of
this AD is affected, the owner/operator must use the authority
provided in paragraph (e) of this AD to request approval from the
FAA. This approval may address either no action, if the current
configuration eliminates the unsafe condition; or different actions
necessary to address the unsafe condition described in this AD. Such
a request should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any airplane from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent degradation of the landing capability of the
airplane, accomplish the following:
(a) Within 24 hours after February 6, 1995 (the effective date
of AD 94-26-51, amendment 39-9120), revise the Limitations Section
of the FAA-approved MD-11 Airplane Flight Manual (AFM), page 5-3,
Flight Guidance, Automatic Landing Section, to include the following
restriction. This may be accomplished by inserting a copy of this AD
in the AFM.
``Autoland operation below 100 feet above ground level (AGL) is
prohibited. The autopilot must be disconnected prior to descent
below 100 feet AGL.''
(b) For airplanes on which the inspections and tests specified
in paragraph (b) of AD 94-26-51, amendment 39-9120, (and reiterated
below) have been initiated prior to the effective date of this AD:
Accomplishment of the inspections and tests specified in paragraphs
(b)(1) and (b)(2) of this AD, in accordance with McDonnell Douglas
MD-11 Alert Service Bulletin A34-57, dated December 19, 1994,
temporarily terminates the AFM revision required by paragraph (a) of
this AD. These inspections and tests must be repeated at intervals
not to exceed 500 hours time-in-service. As of 60 days after the
effective date of this AD, however, those actions no longer
constitute terminating action for paragraph (a) of this AD. As of 60
days after the effective date of this AD, only the actions specified
in paragraph (c) of this AD constitute such terminating action.
(1) Perform an inspection to determine if the connector nut of
the four coaxial connectors on the back of the radio altimeter
receiver/transmitter is loose.
(i) If no loose nut is found, prior to further flight, loosen
the nut until finger tight, retorque the nut to 10 to 15 inch
pounds, and mark the nut with a torque stripe.
Note 2: Retorque is not necessary during repetitive inspections
if the torque stripe is in line, as specified in the alert service
bulletin.
(2) Perform a leakage indication test to verify the integrity of
the radio altimeter antenna system. Prior to further flight, correct
any discrepancy found.
[[Page 39631]]
(c) Accomplishment of the actions specified in paragraphs
(c)(1), (c)(2), and (c)(3) of this AD, as applicable, constitutes
terminating action for the AFM revision required by paragraph (a) of
this AD, and for the repetitive inspections and tests specified in
paragraph (b) of this AD. Following accomplishment of the actions
specified in this paragraph, the AFM revision may be removed from
the AFM.
(1) For airplanes equipped with Allied Signal radio altimeters:
Replace radio altimeters 1 and 2 located in the center accessory
compartment with modified radio altimeters, in accordance with
McDonnell Douglas Service Bulletin MD11-34-063, dated July 10, 1995.
The requirements of this paragraph must be accomplished prior to or
in conjunction with paragraph (c)(3) of this AD.
(2) For all airplanes: Perform an inspection to identify the
part number (P/N) of the coaxial cables of the radio altimeter in
accordance with McDonnell Douglas Service Bulletin MD11-34-060,
Revision 3, dated July 14, 1995. The requirements of this paragraph
must be accomplished prior to or in conjunction with paragraph
(c)(3) of this AD.
(i) For Group 1, 2, and 4 airplanes: Prior to further flight,
accomplish either paragraph (c)(2)(i)(A) or (c)(2)(i)(B) of this AD,
as applicable, in accordance with the service bulletin.
(A) If the cables are identified as P/N AE11532-1, -2, -3, or -
4, install new clamps, replace the cables with new cables, and
perform an inspection to verify if lockwashers having P/N MS51848-45
are installed on the coaxial contacts.
(1) If no lockwasher is installed, prior to further flight,
install a lockwasher having P/N MS51848-45 and install the coaxial
contact, in accordance with the service bulletin.
(2) If a lockwasher having P/N MS51848-45 is installed, prior to
further flight, install the coaxial contact in accordance with the
service bulletin.
(B) If the cables are identified as P/N AE11919-1, -2, -3, or -
4, install the new clamps.
(ii) For Group 3 airplanes: Prior to further flight, accomplish
either paragraph (c)(2)(ii)(A) or (c)(2)(ii)(B) of this AD, as
applicable, in accordance with the service bulletin.
(A) If the cables are identified as P/N AE11532-1, -2, -3 or -4,
install the new clamps, replace the cables with new cables, perform
an inspection to verify if lockwashers having P/N MS51848-45 are
installed on the coaxial contacts, and replace the brackets of the
terminal grounding block with a new bracket and relocate them, in
accordance with the service bulletin.
(1) If no lockwasher is installed, prior to further flight,
install a lockwasher having P/N MS51848-45 and install the coaxial
contact, in accordance with the service bulletin.
(2) If a lockwasher having P/N MS51848-45 is installed, prior to
further flight, install the coaxial contact in accordance with the
service bulletin.
(B) If the cables are identified as P/N AE11919-1, -2, -3, or -
4, install the new clamps, and replace the brackets of the terminal
ground block with new brackets and relocate them, in accordance with
the service bulletin.
(3) For all airplanes: Update the software of the two flight
control computers (FCC) having part number (P/N) 4059001-904 or -
905, and reidentify them as P/N 4059001-906, in accordance with
McDonnell Douglas Service Bulletin MD11-22-015, dated July 3, 1995.
The requirements of paragraphs (c)(1) and/or (c)(2), as applicable,
must be accomplished prior to or in conjunction with this paragraph.
(d) Within 10 days after accomplishing the inspection required
by paragraph (b)(2) of this AD, submit a report of the inspection
results (both positive and negative findings) to the Manager, Los
Angeles Aircraft Certification Office (ACO), 3960 Paramount
Boulevard, Lakewood, California 90712; fax (310) 627-5210.
Information collection requirements contained in this regulation
have been approved by the Office of Management and Budget (OMB)
under the provisions of the Paperwork Reduction Act of 1980 (44
U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-
0056.
(e) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used if approved by the Manager, Los Angeles ACO. Operators shall
submit their requests through an appropriate FAA Principal
Maintenance Inspector, who may add comments and then send it to the
Manager, Los Angeles ACO.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Los Angeles ACO.
(f) Special flight permits may be issued in accordance with
sections 21.197 and 21.199 of the Federal Aviation Regulations (14
CFR 21.197 and 21.199) to operate the airplane to a location where
the requirements of this AD can be accomplished.
(g) The actions shall be done in accordance with McDonnell
Douglas MD-11 Alert Service Bulletin A34-57, dated December 19,
1994; McDonnell Douglas Service Bulletin MD11-34-063, dated July 10,
1995; McDonnell Douglas Service Bulletin MD11-34-060, Revision 3,
dated July 14, 1995; and McDonnell Douglas Service Bulletin MD11-22-
015, dated July 3, 1995. The incorporation by reference of McDonnell
Douglas MD-11 Alert Service Bulletin A34-57, dated December 19,
1994, was approved previously by the Director of the Federal
Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 as of
February 6, 1995 (60 FR 4076, January 20, 1995). The incorporation
by reference of the remainder of the service documents listed above
was approved by the Director of the Federal Register in accordance
with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from
McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach,
California 90846, Attention: Technical Publications Business
Administration, Dept. C1-L51 (2-60). Copies may be inspected at the
FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington; or at FAA, Transport Airplane Directorate, Los Angeles
Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood,
California; or at the Office of the Federal Register, 800 North
Capitol Street, NW., suite 700, Washington, DC.
(h) This amendment becomes effective on August 18, 1995.
Issued in Renton, Washington, on July 21, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-18434 Filed 8-2-95; 8:45 am]
BILLING CODE 4910-13-U